Step 1: Materials
For tools, you will see I am using a simple v block to cut the coin on made of a piece of oak. It will really help having this to support the coin as you cut it. You will see other people using a device that sort of pinches the coin while you work on it. That will save you a lot of strain, but if you hardly ever cut coins it might not be worth the investment.
The three main tools you will need for cutting it out will be a drill with some pretty small bits, a jeweler's saw, and a bunch of files. I used a dremel with a 61 gauge drill bit I think. While using the jeweler's saw, you will go through blades extremely fast. I think I snapped about 5 blades, so have extra blades, 4/0 size is probably the best. Files may be useful to help smooth things out when you are done, but I didn't have too much need for them.
I also used a bit of silver plated wire to create something to allow this to be put on a chain. I think the drill hole was about 1mm, finding a chain that thin would be a pain, so creating something to allow this coin to hang from will make this a better pendant. I used a toothpick to bend the wire around, and a pair of wire clippers to cut the ends off.
Step 2: Drilling the Starter Hole
It would be helpful to put the coin in some sort of vise while you do this step, as well as probably safer. Safety goggles are a must though as when drill bits are this thin they are very prone to snapping and you don't want either a piece of the coin or a drill bit in your eye.
Step 3: Cutting Out the Coin
One major consideration when looking at what you can and cannot cut out is the thickness of the piece. You will have a very fragile pendant if you make very thin parts in your design, which can bend or snap off. Looking at my design, you can see the tail gets fairly thin by the end. I ended up slightly bending it downward cutting the tail out, so I had to bend it back. If it was any thinner it might just have snapped.
To use the jeweler's saw. you first clamp down the top of the blade in the top screw, making the teeth of the blade face outwards. You then thread the blade through the hole if you are cutting the inside of a coin. You then clamp the bottom of the blade. The screw on the back of some saws can be used to adjust the tension of the blade.
Saw blades should be lubricated when you first use them, but you can use wax to re-lubricate it later on. To saw, you keep the blade perpendicular to the coin, and then you start just sawing up and down with a smooth motion. You will be able to hear and feel when the blade is sawing correctly, it will not be a jarring motion and it will have a distinct sound.
While cutting with on a v block you hold the coin against the wood with one hand while sawing with the other. I found I can do this pretty well using either hand holding or sawing. The coin is held so most of it is supported on the block while the part you are cutting is inside the v. Your finger holding the coin down might get pretty strained, I found switching which hand is cutting and which is holding the coin helps alleviate this. Of course getting one of the devices that holds the coin hands free would be also easier if you want to pay for one of those
My first pass at cutting the ring out particularly on the left side was pretty bad, so I had to go back in and saw out more to make it more smooth. One thing that kind of screwed me up is I let to much metal filings build up on the top of the coin and I couldn't see exactly what I was doing, so my accuracy suffered a little bit.
An important thing is to remember to enough metal attaching your coin to the rim. This should also be wide enough that you can drill a hole to mount the pendant from.
Step 4: Finishing the Cutting and Drilling the Hole for the Wire
I drilled this between two spikes on top of the head of the seahorse. As you can see in the picture on the previous picture I had left some work cutting to the left of the drill hole. I finished this up. but by this time I actually had run out of saw blades, so I had to recycle one that had snapped off already. It works in a pinch, but I would recommend starting with a dozen or so blades so you don't run into this problem.
Step 5: Wiring the Pendant and Presentation
I thought making a little gift box would be nice for this pendant, so I made the masu box out of a 6 inch square piece of purple origami paper and made the matching lid to go with it. I also made a little seahorse I looked up on youtube out of a 2 inch square of paper. this I glued onto the box with rubber cement. I put some blue tissue paper in the box when I was done to rest the coin on.
Thanks for reading my first instructables, I hope this is helpful. It might be helpful to look up a few videos on using a jeweler's saw to help you, I'm not sure how well I could explain it, this is my first time doing a project with one. The project takes a few hours and requires a jeweler's saw which you may not have, but I think these make very nice gifts.